Two hydrogen atoms interact to form a hydrogen molecule. Classify the following statements that describe the stages of bond formation in a hydrogen molecule according to the predominant force existing between the two hydrogen atoms...?

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1 Answer
Nov 23, 2016

Answer:

Here's what I got.

Explanation:

Based on the explanation listed , I assume that you were given a graph similar to this one

https://saylordotorg.github.io/text_general-chemistry-principles-patterns-and-applications-v1.0/s12-05-lewis-structures-and-covalent-.html

The first mistake that you made here was placing

The two hydrogen atoms form a stable hydrogen molecule

in this category

There is no interaction between the two atoms #color(red)(xx)#

The fact that the two atoms are bonded to each other would definitely register as an interaction. The atoms cannot bond andnot interact with each other.

Instead, that option should be placed in this category

Attractive and repulsive forces balance each other #color(green)(sqrt())#

Think of it like this -- the attractive forces are drawing the two atoms closer to each other, while the repulsive forces are pushing them apart.

In order for the two atoms to form a stable bond, these two forces must balance each other out.

The second mistake was placing

The two hydrogen atoms start to combine to form a hydrogen molecule

in this category

Attractive and repulsive forces balance each other #color(red)(xx)#

The key here is the fact that the two atoms start to combine to form the molecule. In order for this to happen, the attractive forces must overpower the repulsive forces.

In other words, the attractive forces must bring the two atoms close enough to allow for the bonding to take place.

Therefore, the correct category would be

Attractive force is predominant between the two atoms #color(green)(sqrt())#

And there you have it. You did get the rest right. Key points to remember here

  • the attractive forces must overpower the repulsion forces in order for bonding to be able to occur
  • the potential energy of the system is at its minimum when the bond is formed because the attractive and repulsive forces balance each other out
  • the potential energy is positive when the repulsion forces overpower the attractive forces because the distance between the two atoms is smaller than the bond length